1561200016 has 10 divisors (see below), whose sum is σ = 3024825062. Its totient is φ = 780600000.

The previous prime is 1561200013. The next prime is 1561200019. The reversal of 1561200016 is 6100021651.

It is an interprime number because it is at equal distance from previous prime (1561200013) and next prime (1561200019).

It can be written as a sum of positive squares in only one way, i.e., 1210761616 + 350438400 = 34796^2 + 18720^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1561200016.

It is not an unprimeable number, because it can be changed into a prime (1561200013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48787485 + ... + 48787516.

Almost surely, 2^1561200016 is an apocalyptic number.

1561200016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1561200016 is a deficient number, since it is larger than the sum of its proper divisors (1463625046).

1561200016 is an equidigital number, since it uses as much as digits as its factorization.

1561200016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97575009 (or 97575003 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 1561200016 is about 39512.0236889988. The cubic root of 1561200016 is about 1160.0753062486.

Adding to 1561200016 its reverse (6100021651), we get a palindrome (7661221667).

The spelling of 1561200016 in words is "one billion, five hundred sixty-one million, two hundred thousand, sixteen".